1. Field of the Invention
The invention relates to an electric fuse having a housing which encases a fuse element located in a chamber. The fuse element melts and thus cuts out the fuse under an overcharge, whereby the temperature and pressure in the interior of the chamber will abruptly rise.
If the pressure developed in the chamber on cutting out a fuse exceeds a given limit, the housing is destroyed in an explosion-like manner. If the housing e.g. comprises a base and a cap, which engages over the base and is fixed thereto to form the chamber, the cap is blown off the base if the internal pressure of the chamber rises beyond a given limit. The switching or breaking capacity of a fuse is decisively dependent on the internal pressure of the chamber which occurs on reaching a corresponding cutout current and which can be sustained by the housing without a destruction risk.
2. Prior Art
Numerous different measures are known for preventing or at least delaying the rapid rise of the chamber internal pressure on cutting out the fuse, so as to increase the switching capacity of the latter. These measures can only be carried out on a limited number of fuse types and also only allow a limited increase in the fuse switching capacity.